99 challenger

[phil tiehen]

have twin rotax, one seems to foul plugs,any additives for ethonal to help?

 

[Dr Honda]

Ethanol won't foul plugs... but Marine Stay-Bil will help with the newer auto fuels.

If it's fouling plugs... I would check the oil injection pump to make sure it's set properly, and that the cable is moving the arm properly.